Foreign Animal Disease (FAD)

Investigation Guidance - HPAI 

April 2022

Please note: This procedure may be revised as needed. 

Page 1 of 3

The National Animal Health Laboratory Network (NAHLN) is a partnership of state and federal diagnostic 

laboratories that provides investigational and surveillance testing for high consequence agricultural 

pathogens. In the event of an animal disease outbreak, early detection is critical to contain the disease as 

quickly as possible. 

The FAD investigation period is defined as the time from when the Area Veterinarian in Charge (AVIC) and 

State animal health official (SAHO) initiates a field FAD investigation until the time the FAD is ruled out or 

confirmed by the FAD field investigation, official National Veterinary Services Laboratories (NVSL) 

reference laboratory diagnostic testing, and/or by official VS case definitions. 

NAHLN laboratories should refer to the current version of the NAHLN Laboratory Guide for Foreign Animal 

Disease (FAD) Investigations (NVSL-MAN-0028); however, there are specific changes in the guidance for 

handling an FAD investigation during the current Highly Pathogenic Avian Influenza (HPAI) outbreak. These 

changes are identified below in Red: 

A. Initiation of an FAD Investigation

• Only initiated by AVIC, SAHO, or designated official: 

• Based on observations in the field. 

• Based on findings of a NAHLN Laboratory Diagnostician. 

• Each FAD is assigned an FAD Investigation number (EMRS Referral Control Number)

• NOTE: FADI samples without an FAD Investigation number should not be tested – 

contact your state’s AVIC, SAHO, or FAD Diagnostician to obtain one. 

• Cases that do not need an FAD number:

• Wild bird morbidity/mortality events should not be assigned an FAD number.

• Testing for domestic poultry (commercial, backyard flocks) associated with the infected 

premises, the associated control area, surveillance zone, and trace-outs for the current 

HPAI incident.

B. Priority

• Priority 1 – High suspicion, Rapid/extraordinary sample collection and transport

• Test immediately

• The NAHLN lab director or designee must email the NAHLN Coordinator / Associate 

Coordinators when testing begins (NAHLN.Coordinators@usda.gov ) 

• Priority A – Intermediate/low suspicion, Commerce adversely affected

• Test immediately

• The NAHLN lab director or designee must email the NAHLN Coordinator / Associate 

Coordinators when testing begins (NAHLN.Coordinators@usda.gov ) 
Foreign Animal Disease (FAD)

Investigation Guidance - HPAI 

April 2022

Please note: This procedure may be revised as needed. 

Page 2 of 3

• Priority 2 – Intermediate suspicion, Commerce not adversely affected

• Test as soon as possible within normal business hours (same day, following day, 

weekends as needed)

• The NAHLN lab director or designee is encouraged email the NAHLN Coordinator / 

Associate Coordinators when testing begins (NAHLN.Coordinators@usda.gov ) 

• Priority 3 – Low suspicion, commerce not adversely affected

• Test within routine accession order

C. Submitting Samples to NVSL Reference Laboratory

• If sample material is insufficient to duplicate by the collector, the entire sample must be sent to 

NVSL’s Reference Laboratory. 

• NVSL sample submission information should be submitted via the NCAH Portal. 

• Level 1 e-Authentication is required for access to the Portal.

• All shipments must include a hard copy 10-4 Form. 

• The NCAH Portal can generate a printable 10-4 Form.

• Email the NVSL Reference Laboratory and the NAHLN Program Office with the information for 

the shipment. Include a scanned copy of the VS 10-4, FedEx or UPS tracking number, and your 

laboratory results if available. If results become available later, please forward results via email, 

including the Ct value, to the following email addresses. 

• NVSL.AI.ND@usda.gov 

• NAHLN.Coordinators@usda.gov 

D. Reporting FADI Results

• All NAHLN labs are expected to message FADI results and associated required data.

• NAHLN laboratories must message presumptive results as NDET (negative) or NONNEG

(presumptive positive) in a final report immediately upon having results available.

• Field specimen ID and Premises ID are necessary so the HPAI testing data can be automatically 

linked with the investigation and response data entered into the EMRS system. 

• NONNEG (presumptive positive) Results:

• NAHLN FADI test results are considered presumptive until NVSL’s confirmation testing is 

completed.

• NDET (negative) Results: 

• NAHLN laboratory results will be final, may send final report. 

• Negative results will be actionable where the State agrees. 

• No further testing will be conducted at NVSL unless requested by the state.
Foreign Animal Disease (FAD)

Investigation Guidance - HPAI 

April 2022

Please note: This procedure may be revised as needed. 

Page 3 of 3

E. Funding and Billing

• NAHLN will reimburse labs for all FAD cases. The FAD number is required. 

• NAHLN will reimburse labs for testing of domestic poultry (commercial, backyard flocks) 

associated with the infected premises, the associated control area, surveillance zone and traceouts for the current HPAI incident. FAD number is not required for these cases. 

• If testing is expected to expand beyond the funds available on your FAD task order, notify the 

NAHLN Program office. An HPAI task order will be issued to reimburse for the testing beyond 

the initial FADI.

• NAHLN will not pay for movement testing.

• NAHLN will not pay for wild bird testing.

• Contact the NAHLN Program Office: 

• To check the status of the current FAD Task Order to assure funds are available prior to 

testing. Tari.A.Moody@usda.gov

• Urgent questions/Need a task order ASAP: NAHLN.Coordinators@usda.gov and 

NAHLN@usda.gov 

• General questions: Tari.A.Moody@usda.gov